SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abf32cd1801ca2c62bf5192cf279804b27b1dafb9c849aa164b981afcddf8b13' 
  AND token = 'X8xW8nP8h7vM2r7nhKYWmwv/06oeMpWzVFtWmXjFCXA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}